The two factors one- population is increasing, second- agricultural land is decreasing due to urbanization forced us to focus our attention on PGPRs. Of so many experts, authors interacted with Prof. K.V.B.R. Tilak, Emeritus from IARI and presently at Osmania University, Hyderabad and other Prof. Appa Rao Podile working on molecular aspects of PGPRs in University of Hyderabad have suggested that due to indiscriminate use of chemical fertilizers and pesticides, PGRR health s are adversely affected resulting the quality and quantity of agricultural produce. As such, one of the authors has accepted the challenge and working on various aspects of PGPR including the nanotechnological initiatives under the supervision of first author. The relevant information has been compiled along with critical analysis in the form of present book which will be useful for researches, farmers and as well as for amateurs or budding scientists.